GRAND RAPIDS, MI -- Connor Stehle watched and waited for his dad to replace the sagging net on the family ping-pong table in the basement of their Hamilton home.

But when nothing materialized, the 11-year-old turned the space into what could grow into a lifetime hobby -- model railroading.

Connor and his grandfather, Rich Stehle, 66, are just two of thousands expected to visit downtown Grand Rapids this weekend to climb aboard the 77th Annual Grand Rails National, sponsored by the National Model Railroad Association.

More than 100 exhibitors manning some 255 booths inside the DeVos Convention Center are luring young and old alike to a cornucopia of model railroad products, displays and services.

"A lot of book vendors, too," said Tom Draper, chairman of the show. "I just spent a small fortune myself."

The show continues Saturday from 10 a.m. until 6 p.m., and concludes Sunday, 10 a.m. until 5 p.m. Admission is $12 for adults, $11 for seniors, $6 for kids 6 through 12, and free to kids under 6.

In essence, the show is a study in minutiae. There are no actual trains on display, but hundreds of layouts built to various scales, featuring cities and rural environs with painstaking detail, right down to the sort of vegetation that lines the tracks.

In young Connor's case, he's slowly transformed the once-hapless ping-pong table into a track and train that also boasts a fire station, school, sawmill, farm, village and beach.

What more could he ask for?

"I kinda want to add an Army base," he said, "and a tunnel for the train to go through."

Connor's grandfather tried his hand at building some items from scratch, but even he admitted that his Styrofoam entities didn't come close to the sort of commercial features that model railroaders can spent thousands on.

The layouts I spied on Friday virtually took my breath away. We're talking about men (and some women) so detail-oriented that they use micrometers and magnifying lenses to re-create people and places and things to every exact dimension.

Last year's show, held in Sacramento, drew some 20,000. Robert Amsler, manager of the NMRA's meetings & trade shows department, estimated that Grand Rapids would bring upwards of 15,000.

Draper and Amsler both hope that number includes youngsters as well as old-timers.

"We try to plant the seed," said Draper, acknowledging that a kid's interest in trains might wane during his teen years, "but then about 30 or 35, they get some disposable income, and the seed blossoms and they're back to model railroading."

One of the show's biggest draws will likely be a huge display constructed almost entirely of Lego blocks -- "a half-million, minimum," estimated one of the dozen men who spent nearly 9 hours erecting the display. "That little truck alone," he said, pointing, "has 300 pieces in it."

Put together by members of the Michigan Lego Users Group, it boasts a to-scale replica of the Penobscot Building in Detroit, among other Michigan landmarks.

"This is a lifestyle," said Scot Thompson, president of the 37-member group.

Aside from displays, there were dozens of vendors offering all kinds of upgrades for model railroaders interested in amping up their collections.

And for model railroaders interested in wearing their hobby on their sleeve, there were products for that, too -- literally.

Jackets featuring fabled railway logos were going for well over $150. Caps were a big draw, as were stickers and decals.